Wrapping up another mind-bending season, the acclaimed Fringe continues to explore otherworldly cases with endless impossibilities. Set in two parallel universes, the FBI's Fringe Division focuses around Special Agent Olivia Dunham, eccentric "fringe" scientist Walter Bishop and his jack-of- all-trades son, Peter - supervised by Special Agent Phillip Broyles and assisted by Agent Astrid Farnsworth.
Just one week after Peter Bishop (Joshua Jackson) saved the day and was then wiped from existence, the truce between the two worlds remains intact, and the two sides are forced to work together. Lincoln Lee (Seth Gabel) joins the Fringe team as they investigate a shapeshifter case that is very personal to him.
As the victims of a highly intelligent serial killer “Over There” stack up, the Fringe Division “Over Here” is asked to assist. As the two sides tangle and innocent people remain at risk, the suspect’s doppelganger “Over Here,” a professor who teaches Forensic Psychology, is brought into the fold and forces the team to consider the notion of sending civilians to the other side.
When two 12-year-old kids bully another boy, they are found dead, and just hours after dying their bodies are shockingly in an advanced state of decomposition. As the Fringe team investigates the mysterious case, they uncover an amorphous figure claiming more victims. Meanwhile, Walter (John Noble) becomes increasingly distracted by his hallucinations.
Olivia (Anna Torv) uncovers a dangerous force that may be connected to Walter’s (John Noble) past experiments with the drug Cortexiphan. Their investigation forces Walter to leave the lab for the first time in years as he and Olivia head to Massive Dynamic in New York to examine old case files. Walter struggles with life outside the lab as he comes face-to-face with the demons of his past.
In the aftermath of recent shocking events, things really escalate when the translucent shapeshifters return. As the threat and circumstances intensify, a former Massive Dynamic scientist Malcolm Truss (guest star Arye Gross) enters the fold. Meanwhile, Nina Sharp pays Walter a visit in the lab.
Real-life spouses Stephen Root and Romy Rosemount guest-star in an all-new FRINGE, which marks the first time the accomplished actors have ever acted together. The Fringe team must find the pattern between tragic time loop anomalies. As the investigation unfolds, Raymond (guest star Root), an electrical engineer, and his wife, Kate (guest star Rosemont), a professor of theoretical physics, enter the picture.
When a man mysteriously dies by an invisible force, his body rapidly begins turning ghostly white. The Fringe team learns that this is not an isolated incident, and there’s evidence that links the predator to someone who passed away with an unknown genetic disorder. Meanwhile, Olivia (Anna Torv) suffers from migraines.
In an effort to find a way home, Peter (Joshua Jackson) journeys to the Other Side to confront Walternate (John Noble). His venture proves more dangerous than expected. Meanwhile, Olivia (Anna Torv) receives a dire premonition from an Observer.
Peter’s (Joshua Jackson) visit to the other side intensifies as the alternate FRINGE Division faces off against a formidable new foe in a harrowing race against time.
Olivia (Anna Torv) continues to cope with the ominous warning from the Observers, while Peter (Joshua Jackson) and the team track a girl with the mysterious ability to predict death.
Our Astrid (Jasika Nicole) gets an unexpected visit from her Alternate, while Peter (Joshua Jackson) and Olivia (Anna Torv) track a killer using a toxin that has yet to be invented. Both universes collide in a case that pushes the boundaries of what is possible.
Peter, Olivia and Walter (John Noble) come face-to-face with a mysterious and terrifying Fringe event as they get trapped in a town from which there’s no escape.
As the Fringe team investigates a mentally ill patient (guest star Harrison Thomas) who appears to be connected to a series of murders, frightening clues and connections are uncovered that lead Olivia to some shocking revelations.
Peter and the Fringe team take extraordinary measures in an attempt to stop life-threatening events.
Following the recent shocking revelations and emotional events, Peter weighs his options as the Fringe team investigates a killer targeting love.
The Fringe team faces a case that appears familiar to Peter. Strangely, it takes place in this world.
Lincoln travels to the other side to join forces with Bolivia and his own alternate, as they search for a vigilante with a surprising connection to the shapeshifters.
Walter travels to the Alternate Universe to assist in the investigation of a Fringe event with ties to both worlds. Meanwhile, David Robert Jones reveals his next target.
This mind-bending 19th episode continues as the story jumps ahead to 2036, when the Observers and the Fringe team engage in a game-changing battle.
The teams on both sides fight on for a common cause, and there are shocking developments tied to the Cortexiphan children.
A mysterious Fringe event causing people to spontaneously combust forces Walter to revisit his painful past while the Fringe team faces off against David Robert Jones to save the world.
In the climactic conclusion of the Season Four finale, the Fringe team is pushed to their breaking point as they desperately attempt to prevent a catastrophic event that threatens the lives of everyone.